State dependence of stimulus-induced variability tuning in macaque MT
Fig 4
Mean-matched Fano factors preserve variability tuning.
(A) Histograms of spike counts by neuron for a given stimulus direction (left: −90°; center: preferred direction; right: + 90°) for alert (blue, throughout) and anesthetized (orange, throughout) recordings. The overlapping area is shown in gray. (B) Sample mean-matched Fano factors, with spike count distributions corresponding to the gray histograms in (A). Each circle is a sample mean. Dashed traces indicate the mean Fano factor across directions. Solid traces indicate the mean Fano factor across bootstrapped samples. (C) Fano factor tuning index (FFTI) of bootstrapped resamples for alert (FFTI = 0.143, s.d. = 0.106) and anesthetized states (FFTI = −0.020, s.d. = 0.057). (D) Distributions of FFTI for mean-matched data samples. Solid traces indicate a best-fit Gaussian curve.